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/Scala 2.12 Library

Class scala.Boolean

Companion object Boolean

abstract final class Boolean extends AnyVal

Boolean (equivalent to Java's boolean primitive type) is a subtype of scala.AnyVal. Instances of Boolean are not represented by an object in the underlying runtime system.

There is an implicit conversion from scala.Boolean => scala.runtime.RichBoolean which provides useful non-primitive operations.

Source
Boolean.scala
Linear Supertypes

Abstract Value Members

abstract def !=(x: Boolean): Boolean

Compares two Boolean expressions and returns true if they evaluate to a different value.

a != b returns true if and only if

    a is true and b is false or a is false and b is true.

abstract def &(x: Boolean): Boolean

Compares two Boolean expressions and returns true if both of them evaluate to true.

a & b returns true if and only if

    a and b are true.
Note

This method evaluates both a and b, even if the result is already determined after evaluating a.

abstract def &&(x: Boolean): Boolean

Compares two Boolean expressions and returns true if both of them evaluate to true.

a && b returns true if and only if

    a and b are true.
Note

This method uses 'short-circuit' evaluation and behaves as if it was declared as def &&(x: => Boolean): Boolean. If a evaluates to false, false is returned without evaluating b.

abstract def ==(x: Boolean): Boolean

Compares two Boolean expressions and returns true if they evaluate to the same value.

a == b returns true if and only if

    a and b are true or a and b are false.

abstract def ^(x: Boolean): Boolean

Compares two Boolean expressions and returns true if they evaluate to a different value.

a ^ b returns true if and only if

    a is true and b is false or a is false and b is true.

abstract def unary_!: Boolean

Negates a Boolean expression.

- !a results in false if and only if a evaluates to true and - !a results in true if and only if a evaluates to false.

returns

the negated expression

abstract def |(x: Boolean): Boolean

Compares two Boolean expressions and returns true if one or both of them evaluate to true.

a | b returns true if and only if

    a is true or b is true or a and b are true.
Note

This method evaluates both a and b, even if the result is already determined after evaluating a.

abstract def ||(x: Boolean): Boolean

Compares two Boolean expressions and returns true if one or both of them evaluate to true.

a || b returns true if and only if

    a is true or b is true or a and b are true.
Note

This method uses 'short-circuit' evaluation and behaves as if it was declared as def ||(x: => Boolean): Boolean. If a evaluates to true, true is returned without evaluating b.

Concrete Value Members

final def !=(arg0: Any): Boolean

Test two objects for inequality.

returns

true if !(this == that), false otherwise.

Definition Classes
Any

final def ##(): Int

Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

returns

a hash value consistent with ==

Definition Classes
Any

def +(other: String): String

Implicit
This member is added by an implicit conversion from Boolean to any2stringadd[Boolean] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd

def ->[B](y: B): (Boolean, B)

Implicit
This member is added by an implicit conversion from Boolean to ArrowAssoc[Boolean] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations
@inline()

def <(that: Boolean): Boolean

Returns true if this is less than that

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
Ordered

def <=(that: Boolean): Boolean

Returns true if this is less than or equal to that.

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
Ordered

final def ==(arg0: Any): Boolean

Test two objects for equality. The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

returns

true if the receiver object is equivalent to the argument; false otherwise.

Definition Classes
Any

def >(that: Boolean): Boolean

Returns true if this is greater than that.

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
Ordered

def >=(that: Boolean): Boolean

Returns true if this is greater than or equal to that.

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
Ordered

final def asInstanceOf[T0]: T0

Cast the receiver object to be of type T0.

Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

returns

the receiver object.

Definition Classes
Any
Exceptions thrown

ClassCastException if the receiver object is not an instance of the erasure of type T0.

def booleanValue(): Boolean

Implicit
This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
Definition Classes
Boolean

def compare(y: Boolean): Int

Result of comparing this with operand that.

Implement this method to determine how instances of A will be sorted.

Returns x where:

    x < 0 when this < that x == 0 when this == that x > 0 when this > that
Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
OrderedProxyOrdered

def compareTo(arg0: java.lang.Boolean): Int

Implicit
This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
Definition Classes
Boolean → Comparable

def compareTo(that: Boolean): Int

Result of comparing this with operand that.

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
Ordered → Comparable

def ensuring(cond: (Boolean) ⇒ Boolean, msg: ⇒ Any): Boolean

Implicit
This member is added by an implicit conversion from Boolean to Ensuring[Boolean] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: (Boolean) ⇒ Boolean): Boolean

Implicit
This member is added by an implicit conversion from Boolean to Ensuring[Boolean] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: Boolean, msg: ⇒ Any): Boolean

Implicit
This member is added by an implicit conversion from Boolean to Ensuring[Boolean] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def ensuring(cond: Boolean): Boolean

Implicit
This member is added by an implicit conversion from Boolean to Ensuring[Boolean] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring

def equals(arg0: Any): Boolean

Compares the receiver object (this) with the argument object (that) for equivalence.

Any implementation of this method should be an equivalence relation:

    It is reflexive: for any instance x of type Any, x.equals(x) should return true.It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true.It is transitive: for any instances x, y, and z of type Any if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.

If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is usually necessary to override hashCode to ensure that objects which are "equal" (o1.equals(o2) returns true) hash to the same scala.Int. (o1.hashCode.equals(o2.hashCode)).

returns

true if the receiver object is equivalent to the argument; false otherwise.

Definition Classes
Any

def formatted(fmtstr: String): String

Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).

Implicit
This member is added by an implicit conversion from Boolean to StringFormat[Boolean] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations
@inline()

def getClass(): Class[Boolean]

Returns the runtime class representation of the object.

returns

a class object corresponding to the runtime type of the receiver.

Definition Classes
BooleanAnyValAny

def hashCode(): Int

Calculate a hash code value for the object.

The default hashing algorithm is platform dependent.

Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.

returns

the hash code value for this object.

Definition Classes
Any

final def isInstanceOf[T0]: Boolean

Test whether the dynamic type of the receiver object is T0.

Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

returns

true if the receiver object is an instance of erasure of type T0; false otherwise.

Definition Classes
Any

val self: Boolean

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Definition Classes
RichBooleanTypedProxy

def toString(): String

Returns a string representation of the object.

The default representation is platform dependent.

returns

a string representation of the object.

Definition Classes
Any

def [B](y: B): (Boolean, B)

Implicit
This member is added by an implicit conversion from Boolean to ArrowAssoc[Boolean] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc

Shadowed Implicit Value Members

def equals(arg0: Any): Boolean

The equality method for reference types. Default implementation delegates to eq.

See also equals in scala.Any.

returns

true if the receiver object is equivalent to the argument; false otherwise.

Implicit
This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
(boolean: java.lang.Boolean).equals(arg0)
Definition Classes
Boolean → AnyRef → Any

def hashCode(): Int

The hashCode method for reference types. See hashCode in scala.Any.

returns

the hash code value for this object.

Implicit
This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
(boolean: java.lang.Boolean).hashCode()
Definition Classes
Boolean → AnyRef → Any

def toString(): String

Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.

returns

a String representation of the object.

Implicit
This member is added by an implicit conversion from Boolean to java.lang.Boolean performed by method boolean2Boolean in scala.Predef.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
(boolean: java.lang.Boolean).toString()
Definition Classes
Boolean → AnyRef → Any

def toString(): String

Returns a string representation of the object.

The default representation is platform dependent.

returns

a string representation of the object.

Implicit
This member is added by an implicit conversion from Boolean to RichBoolean performed by method booleanWrapper in scala.LowPriorityImplicits.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
(boolean: RichBoolean).toString()
Definition Classes
ProxyAny

© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.12.9/scala/Boolean.html